The proposed system allows for the delivery of Internet data via CATV's “broadband coax infrastructure”, in a more cost effective deployment than today's “conventional” broadband infrastructure implementation. To highlight the differences, let's first begin by reviewing the current broadband infrastructure.
FIG. 1 highlights the “last mile” of a prior typical high speed broadband system implementation as presently used. As shown, the portion of the system included in the CATV providers main distribution line, includes a fiber node 2 for receiving from a fiber optic cable 1 light modulated signals from the headend of the provider, and converting the light signals to RF output signals connected to the input of a line extender 4. A coaxial cable 5 feeds the output of the line extender to the input of a CATV tap 6. The CATV tap 6 typically includes a plurality of splitters (not shown) for splitting off a plurality of portions of the CATV signal, the portions being provided at Terminals for connection via coaxial cables to a plurality of houses or facilities, respectively, subscribing to the associated CATV service. As shown in FIG. 1, for purposes of simplified illustration, a first coaxial cable 10 is connected between the CATV tap 6 and a subscriber's house 32, a second coaxial cable 9 also being connected there between. Also, in an nth coaxial cable illustrated as 14, is connected from the CATV tap 6 to an nth subscriber's house, but for practical purposes it should be understood that the number of tap offs provided by CATV tap 6 is limited to the present state-of-the-art. All of the connections between the CATV tap 6 and various homes and/or business establishments of subscribers provides for bidirectional signal transfer there between. Within the subscriber's home 34, the splitter 22 splits off a portion of the CATV signal onto a coaxial cable 24 connection to various TV sets, set-tops, and so forth. Splitter 22 also splits off via coaxial cable 23 CATV signals that are connected to a cable modem 24. In this example, the cable modem 24 converts the CATV RF signals to Ethernet or USB signals which are connected to a Wi-Fi node 26. Also shown within the home 34 is a personal computer (PC 30) that is connected to a Wi-Fi/RF transceiver 28.
With further reference to FIG. 1, it illustrates a CATV tap 6, as well as the subsequent or additional line extender(s) (such as amplifiers, not shown) and CATV system tap(s) (not shown), that would typically be present within the last mile of a CATV network. The specific number of line extenders and taps present in the CATV network is dependent on the distance from the CATV tap 6 to the subscriber homes and/or business establishments, the density of those homes (i.e., homes and/or establishments per given geographic area), and the subscription rate (i.e., number of paying customers) within the geographic area.
Communications signals, i.e., video/audio, high speed data, and control information, are transmitted (and potentially also returned) on the CATV system at prescribed frequencies/wavelengths, as determined by the CATV operator. The exact frequencies and wavelengths of those signals are determined by both industry agreed upon conventions, and the specific bandwidth requirements of each CATV operator. These communication signals on the “right” side of the fiber node 2 (i.e., to/from the “last mile”), are typically transported as RF signal on a coaxial cable, at frequencies consistent with the above, and generally up to 1.2 GHz.
On the left side of the fiber node 2 (i.e., to and from the headend), the signals are generally transported on fiber optic cables 1, using specific industry standard laser wavelengths and modulation, also consistent with the above. These signals may also be transported to/from the headend as RF signals on coaxial cables (at similar or different frequencies than the last mile), or some combination of fiber optic and coaxial cables. Within the fiber node 2 itself, the signals are converted to the “last mile” RF frequencies (regardless of how they might have been received/sent from the CATV headend), and amplified for distribution to the last mile as indicated. Also contained within these signals are control signals to and from the headend to the home(s) which provide for authorization, configuration and control of video/audio set-tops, IP telephony hardware and cable modems, that may be present within the home(s). These signal are generated via a “system controller” present at the CATV headend (or other central location), but not illustrated.
Also shown on FIG. 1 is the typical interfacing into a typical residence via an RF splitter/tap 22, at the point of presence (entry) into the home, of the CATV network. As indicated, this process is “repeated” at other subsequent homes and/or business establishments (to the nth home, for example), from each tap that may be present on the CATV network, for each subscribed (i.e., paying) customer residence. Within each home, this RF splitter 22 “splits” the RF signal into two main functional pathways-the video/audio path via coaxial cable 20 (to the left of the splitter 22), and the high speed data path via coaxial cable 23 (to the right of the splitter 22). There could be additional subsequent (or combination) splits on either/both of these main video/audio and data pathways depending upon the layout of the house and the number of required video/audio and/or data outlets, but this will serve to detail the basic implementation.
The functional pathways can be described simply as those signals delivered in support of video/audio services, such as broadcast/premium channels, or Pay per View/On-Demand channels which are delivered within the video/audio (RF) spectrum on the coax cable 20, and those signals in support of data services, such as high speed data or VoIP telephony, which are delivered within the high speed data (RF) spectrum on the coax cable 23. The reality is that the actual coax cable and the combined video/audio and high speed data signals are identical in both signal pathways, only that the RF signals of each functional pathways are located at different frequencies bands on the CATV coax. Alternatively, the video/audio signals could be delivered as high speed data signals, either as independently delivered (potentially in IP video/audio format) to an IP Video/audio set-top, or as IP video/audio in the DOCSIS (Data Over Cable Service Interface Specification) format.
Inside the home (see FIG. 1), the high speed data pathway has an input to the CATV modem 24, which converts the RF signal to high speed baseband data. The output of the modem 24 then inputs the high speed data into a conventional router 26 (with optional integrated WiFi functionality, as indicated). It should be noted that this WiFi functionality may not be present at all (wherein the router 26 is “hardwired” directly to a computer via Ethernet cable), or the WiFi functionality may be a separate device hardwired to the router via an Ethernet (cable) connection. It should also be noted that the Wi-Fi node 26 could additionally include integrated VoIP functionality, interfacing directly to a telephone (not shown), or this VoIP functionality could be contained within a separate device, hardwired via Ethernet to the router. The WiFi signal is then transmitted wirelessly within the home (primarily), to other WiFi enabled devices in the home, such as computers (desk-tops and/or laptops, such as PC 30 connected to a Wi-Fi/RF transceiver or router 28), video/audio game consoles, smart-phones, tablets, PDA, WiFi enabled TVs and DVD players, etc), via the “IEEE 802.11x” (Institute of Electrical and Electronic Engineers) frequency bands (5.0 and/or 2.4 GHz).